Wireless mobile communication devices, such as smart phone or other mobile devices, may access Internet Protocol (IP) networks using different types of access networks. For example, a mobile device may connect to an IP-based core network using access technologies according to standards such as 3GPP (3rd Generation Partnership Project), 3GPP2 (3rd Generation Partnership Project 2), and WLAN (wireless local area network, such as a Wi-Fi-based WLAN).
The term “mobility management” refers to the ability of a mobile device to keep the same IP address, stay connected, and maintain ongoing applications while roaming between IP networks. Mobility management may be used, for example, in order to enable traffic offloading from a cellular access network (e.g., a 3GPP or 3GPP2 access network) to a WLAN access network. Mobility management can refer to both initial selection of an access network and traffic steering between access networks. “Traffic steering” may refer to dynamically varying the access network that is used for a particular application or packet flow.